NADPH Oxidase‐Dependent NLRP3 Inflammasome Activation and its Important Role in Lung Fibrosis by Multiwalled Carbon Nanotubes

The purpose of this paper is to elucidate the key role of NADPH oxidase in NLRP3 inflammasome activation and generation of pulmonary fibrosis by multi‐walled carbon nanotubes (MWCNTs). Although it is known that oxidative stress plays a role in pulmonary fibrosis by single‐walled CNTs, the role of specific sources of reactive oxygen species, including NADPH oxidase, in inflammasome activation remains to be clarified. In this study, three long aspect ratio (LAR) materials (MWCNTs, single‐walled carbon nanotubes, and silver nanowires) are used to compare with spherical carbon black and silver nanoparticles for their ability to trigger oxygen burst activity and NLRP3 assembly. All LAR materials but not spherical nanoparticles induce robust NADPH oxidase activation and respiratory burst activity in THP‐1 cells, which are blunted in p22^phox‐deficient cells. The NADPH oxidase is directly involved in lysosomal damage by LAR materials, as demonstrated by decreased cathepsin B release and IL‐1β production in p22^phox‐deficient cells. Reduced respiratory burst activity and inflammasome activation are also observed in bone marrow‐derived macrophages from p47^phox‐deficient mice. Moreover, p47^phox‐deficient mice have reduced IL‐1β production and lung collagen deposition in response to MWCNTs. Lung fibrosis is also suppressed by N‐acetyl‐cysteine in wild‐type animals exposed to MWCNTs.     

Polyhydroxylated Metallofullerenols Stimulate IL‐1β Secretion of Macrophage through TLRs/MyD88/NF‐κB Pathway and NLRP3 Inflammasome Activation

Polyhydroxylated fullerenols especially gadolinium endohedral metallofullerenols (Gd@C₈₂(OH)₂₂) are shown as a promising agent for antitumor chemotherapeutics and good immunoregulatory effects with low toxicity. However, their underlying mechanism remains largely unclear. We found for the first time the persistent uptake and subcellular distribution of metallofullerenols in macrophages by taking advantages of synchrotron‐based scanning transmission X‐ray microscopy (STXM) with high spatial resolution of 30 nm. Gd@C₈₂(OH)₂₂ can significantly activate primary mouse macrophages to produce pro‐inflammatory cytokines like IL‐1β. Small interfering RNA (siRNA) knockdown shows that NLRP3 in?ammasomes, but not NLRC4, participate in fullerenol‐induced IL‐1β production. Potassium efflux, activation of P2X₇ receptor and intracellular reactive oxygen speciesare also important factors required for fullerenols‐induced IL‐1β release. Stronger NF‐κB signal triggered by Gd@C₈₂(OH)₂₂ is in agreement with higher pro‐IL‐1β expression than C₆₀(OH)₂₂. Interestingly, TLR4/MyD88 pathway but not TLR2 mediates IL‐1β secretion in Gd@C₈₂(OH)₂₂ exposure confirmed by macrophages from MyD88^?/?/TLR4^?/?/TLR2^?/? knockout mice, which is different from C₆₀(OH)₂₂. Our work demonstrated that fullerenols can greatly activate macrophage and promote IL‐1β production via both TLRs/MyD88/NF‐κB pathway and NLRP3 inflammasome activation, while Gd@C₈₂(OH)₂₂ had stronger ability C₆₀(OH)₂₂ due to the different electron affinity on the surface of carbon cage induced by the encaged gadolinium ion.     

Toxicological Profiling of Highly Purified Single‐Walled Carbon Nanotubes with Different Lengths in the Rodent Lung and Escherichia Coli

Carbon nanotubes (CNTs) exhibit a number of physicochemical properties that contribute to adverse biological outcomes. However, it is difficult to define the independent contribution of individual properties without purified materials. A library of highly purified single‐walled carbon nanotubes (SWCNTs) of different lengths is prepared from the same base material by density gradient ultracentrifugation, designated as short (318 nm), medium (789 nm), and long (1215 nm) SWCNTs. In vitro screening shows length‐dependent interleukin‐1β (IL‐1β) production, in order of long > medium > short. However, there are no differences in transforming growth factor‐β1 production in BEAS‐2B cells. Oropharyngeal aspiration shows that all the SWCNTs induce profibrogenic effects in mouse lung at 21 d postexposure, but there are no differences between tube lengths. In contrast, these SWCNTs demonstrate length‐dependent antibacterial effects on Escherichia coli, with the long SWCNT exerting stronger effects than the medium or short tubes. These effects are reduced by Pluronic F108 coating or supplementing with glucose. The data show length‐dependent effects on proinflammatory response in macrophage cell line and antibacterial effects, but not on collagen deposition in the lung. These data demonstrate that over the length scale tested, the biological response to highly purified SWCNTs is dependent on the complexity of the nano/bio interface.     

Carbon Nanotubes Disrupt Iron Homeostasis and Induce Anemia of Inflammation through Inflammatory Pathway as a Secondary Effect Distant to Their Portal‐of‐Entry

Although numerous toxicological studies have been performed on carbon nanotubes (CNTs), a few studies have investigated their secondary and indirect effects beyond the primary target tissues/organs. Here, a cascade of events are investigated: the initiating event and the subsequent key events necessary for the development of phenotypes, namely CNT‐induced pro‐inflammatory effects on iron homeostasis and red blood cell formation, which are linked to anemia of inflammation (AI). A panel of CNTs are prepared including pristine multiwall CNTs (P‐MWCNTs), aminated MWCNTs (MWCNTs‐NH₂), polyethylene glycol MWCNTs (MWCNTs‐PEG), polyethyleneimine MWCNTs (MWCNTs‐PEI), and carboxylated MWCNTs (MWCNTs‐COOH). It has been demonstrated that all CNT materials provoke inflammatory cytokine interleukin‐6 (IL‐6) production and stimulate hepcidin induction, associated with disordered iron homeostasis, irrespective of exposure routes including intratracheal, intravenous, and intraperitoneal administration. Meanwhile, PEG and COOH modifications can ameliorate the activation of IL‐6‐hepcidin signaling. Long‐term exposure of MWCNTs results in AI and extramedullary erythropoiesis. Thus, an adverse outcome pathway is identified: MWCNT exposure leads to inflammation, hepatic hepcidin induction, and disordered iron metabolism. Together, the combined data depict the hazardous secondary toxicity of CNTs in incurring anemia through inflammatory pathway. This study will also open a new avenue for future investigations on CNT‐induced indirect and secondary adverse effects.     

Modelling the onset of Type 1 diabetes: can impaired macrophage phagocytosis make the difference between health and disease?

A wave of apoptosis (programmed cell death) occurs normally in pancreatic beta-cells of newborn mice. We previously showed that macrophages from non-obese diabetic (NOD) mice become activated more slowly and engulf apoptotic cells at a lower rate than macrophages from control (Balb/c) mice. It has been hypothesized that this low clearance could result in secondary necrosis, escalating inflammation and self-antigen presentation that later triggers autoimmune, Type 1 diabetes (T1D). We here investigate whether this hypothesis could offer a reasonable and parsimonious explanation for onset of T1D in NOD mice. We quantify variants of the Copenhagen model (Freiesleben De Blasio et al. 1999 Diabetes 48, 1677), based on parameters from NOD and Balb/c experimental data. We show that the original Copenhagen model fails to explain observed phenomena within a reasonable range of parameter values, predicting an unrealistic all-or-none disease occurrence for both strains. However, if we take into account that, in general, activated macrophages produce harmful cytokines only when engulfing necrotic (but not apoptotic) cells, then the revised model becomes qualitatively and quantitatively reasonable. Further, we show that known differences between NOD and Balb/c mouse macrophage kinetics are large enough to account for the fact that an apoptotic wave can trigger escalating inflammatory response in NOD, but not Balb/c mice. In Balb/c mice, macrophages clear the apoptotic wave so efficiently, that chronic inflammation is prevented.     

Multiwall Carbon Nanotubes Mediate Macrophage Activation and Promote Pulmonary Fibrosis Through TGF‐β/Smad Signaling Pathway

Multiwall carbon nanotubes (MWCNTs) have been widely used in many disciplines due to their unique physical and chemical properties, but have also raised great concerns about their possible negative health impacts, especially through occupational exposure. Although recent studies have demonstrated that MWCNTs induce granuloma formation and/or fibrotic responses in the lungs of rats or mice, their cellular and molecular mechanisms remain largely unaddressed. Here, it is reported that the TGF‐β/Smad signaling pathway can be activated by MWCNTs and play a critical role in MWCNT‐induced pulmonary fibrosis. Firstly, in vivo data show that spontaneously hypertensive (SH) rats administered long MWCNTs (20–50 μm) but not short MWCNTs (0.5–2 μm) exhibit increased fibroblast proliferation, collagen deposition and granuloma formation in lung tissue. Secondly, the in vivo experiments also indicate that only long MWCNTs can significantly activate macrophages and increase the production of transforming growth factor (TGF)‐β1, which induces the phosphorylation of Smad2 and then the expression of collagen I/III and extracellular matrix (ECM) protease inhibitors in lung tissues. Finally, the present in vitro studies further demonstrate that the TGF‐β/Smad signaling pathway is indeed necessary for the expression of collagen III in fibroblast cells. Together, these data demonstrate that MWCNTs stimulate pulmonary fibrotic responses such as fibroblast proliferation and collagen deposition in a TGF‐β/Smad‐dependent manner. These observations also suggest that tube length acts as an important factor in MWCNT‐induced macrophage activation and subsequent TGF‐β1 secretion. These in vivo and in vitro studies further highlight the potential adverse health effects that may occur following MWCNT exposure and provide a better understanding of the cellular and molecular mechanisms by which MWCNTs induce pulmonary fibrotic reactions.     

Multiwall Carbon Nanotubes Directly Promote Fibroblast–Myofibroblast and Epithelial–Mesenchymal Transitions through the Activation of the TGF‐β/Smad Signaling Pathway

A number of studies have demonstrated that MWCNTs induce granuloma formation and fibrotic responses in vivo, and it has been recently reported that MWCNT‐induced macrophage activation and subsequent TGF‐β secretion contribute to pulmonary fibrotic responses. However, their direct effects against alveolar type‐II epithelial cells and fibroblasts and the corresponding underlying mechanisms remain largely unaddressed. Here, MWCNTs are reported to be able to directly promote fibroblast‐to‐myofibroblast conversion and the epithelial–mesenchymal transition (EMT) through the activation of the TGF‐β/Smad signaling pathway. Both of the cell transitions may play important roles in MWCNT‐induced pulmonary fibrosis. Firstly, in‐vivo and in‐vitro data show that long MWCNTs can directly interact with fibroblasts and epithelial cells, and some of them may be uptaken into fibroblasts and epithelial cells by endocytosis. Secondly, long MWCNTs can directly activate fibroblasts and increase both the basal and TGF‐β1‐induced expression of the fibroblast‐specific protein‐1, α‐smooth muscle actin, and collagen III. Finally, MWCNTs can induce the EMT through the activation of TGF‐β/Smad2 signaling in alveolar type‐II epithelial cells, from which some fibroblasts involved in pulmonary fibrosis are thought to originate. These observations suggest that the activation of the TGF‐β/Smad2 signaling plays a critical role in the process of the fibroblast‐to‐myofibroblast transition and the EMT induced by MWCNTs.     

Mechanistic Differences in Cell Death Responses to Metal‐Based Engineered Nanomaterials in Kupffer Cells and Hepatocytes

The mononuclear phagocyte system in the liver is a frequent target for nanoparticles (NPs). A toxicological profiling of metal‐based NPs is performed in Kupffer cell (KC) and hepatocyte cell lines. Sixteen NPs are provided by the Nanomaterial Health Implications Research Consortium of the National Institute of Environmental Health Sciences to study the toxicological effects in KUP5 (KC) and Hepa 1–6 cells. Five NPs (Ag, CuO, ZnO, SiO₂, and V₂O₅) exhibit cytotoxicity in both cell types, while SiO₂ and V₂O₅ induce IL‐1β production in KC. Ag, CuO, and ZnO induced caspase 3 generated apoptosis in both cell types is accompanied by ion shedding and generation of mitochondrial reactive oxygen species (ROS) in both cell types. However, the cell death response to SiO₂ in KC differs by inducing pyroptosis as a result of potassium efflux, caspase 1 activation, NLRP3 inflammasome assembly, IL‐1β release, and cleavage of gasdermin‐D. This releases pore‐performing peptide fragments responsible for pyroptotic cell swelling. Interestingly, although V₂O₅ induces IL‐1β release and delays caspase 1 activation by vanadium ion interference in membrane Na⁺/K⁺ adenosine triphosphate (ATP)ase activity, the major cell death mechanism in KC (and Hepa 1–6) is caspase 3 mediated apoptosis. These findings improve the understanding of the mechanisms of metal‐based engineered nanomaterial (ENM) toxicity in liver cells toward comprehensive safety evaluation.     

Long‐term effects of angiotensin II blockade with irbesartan on inflammatory markers in hemodialysis patients: A randomized double blind placebo controlled trial (SAFIR study)

Introduction: Low‐grade chronic inflammation is common in hemodialysis (HD) patients. Previous studies suggest an anti‐inflammatory effect of angiotensin II receptor blocker (ARB) treatment. The aim of this study was to compare the effect of ARB vs. placebo on plasma concentrations of inflammatory markers in HD patients. Methods: Adult HD patients were randomized for double‐blind treatment with the ARB irbesartan 150–300 mg/day or placebo. At baseline, 1 week, 3, 6, 9, and 12 months plasma high sensitivity C‐reactive protein (hsCRP), interleukin (IL)?1β, IL‐6, IL‐8, IL‐18, and transforming growth factor‐β (TGF‐β) were measured using Luminex and enzyme‐linked immunosorbent assay (ELISA) technology. Findings: Eighty‐two patients were randomized (placebo/ARB: 41/41). The groups did not differ in initial levels of any of the inflammatory markers (placebo/ARB median(range)): hsCRP 3.3(0.2–23.4)/2.7(0.2–29.6) μg/mL; IL‐1β 1.1(0.0–45.9)/1.1(0.0‐7.2) pg/mL; IL‐6 10(1–90)/12(1–84) pg/mL; IL‐8 31(9–134)/34(5–192) pg/mL; IL‐18 364(188–1343)/377(213–832) pg/mL; TGF‐β 3.2(0.8–13.9)/3.6(1.3–3.8) ng/mL. Overall, there was no significant difference in hsCRP, IL‐6, IL‐8, and TGF‐β between placebo and ARB‐treated patients during the study period, and hsCRP, IL‐6, IL‐8, and TGF‐β were relatively stable during the study period (P ≥ 0.18 in all tests for parallel curves, equal levels, and constant levels). The IL‐1β level was slightly different in the two groups over time, but not significantly (P = 0.09 in test for parallel curves) and it was also relatively stable during the study period (P ≥ 0.49 in tests for equal levels and constant level). IL‐18 was the only inflammatory marker which was not constant during the study period (P = 0.001 in test for constant level), but there was no significant difference between placebo and ARB‐treated (P ≥ 0.51 in tests for parallel curves and equal levels). Discussion: Inflammatory biomarkers were neither acutely, nor in the long‐term significantly affected by the ARB irbesartan. Our findings suggest that ARB treatment in HD patients does not offer protective anti‐inflammatory effects.     

Physicochemical and Biological Properties of Biomimetic Mineralo‐Protein Nanoparticles Formed Spontaneously in Biological Fluids

Recent studies indicate that mineral nanoparticles (NPs) form spontaneously in human body fluids. These biological NPs represent mineral precursors that are associated with ectopic calcifications seen in various human diseases. However, the parameters that control the formation of mineral NPs and their possible effects on human cells remain poorly understood. Here a nanomaterial approach to study the formation of biomimetic calcium phosphate NPs comparable to their physiological counterparts is described. Particle sizing using dynamic light scattering reveals that serum and ion concentrations within the physiological range yield NPs below 100 nm in diameter. While the particles are phagocytosed by macrophages in a size‐independent manner, only large particles or NP aggregates in the micrometer range induce cellular responses that include production of mitochondrial reactive oxygen species, caspase‐1 activation, and secretion of interleukin‐1β (IL‐1β). A comprehensive proteomic analysis reveals that the particle‐bound proteins are similar in terms of their identity and number, regardless of particle size, suggesting that protein adsorption is independent of particle size and curvature. In conclusion, the conditions underlying the formation of mineralo‐protein particles are similar to the ones that form in vivo. While mineral NPs do not activate immune cells, they may become pro‐inflammatory and contribute to pathological processes once they aggregate and form larger mineral particles.     

Up-regulation of T lymphocyte and antibody production by inflammatory cytokines released by macrophage exposure to multi-walled carbon nanotubes

Our data demonstrate that multi-walled carbon nanotubes (MWCNTs) are internalized by macrophages, subsequently activating them to produce interleukin (IL)-12 (IL-12). This cytokine induced the proliferative response of T lymphocytes to a nonspecific mitogen and to ovalbumin (OVA). This increase in the proliferative response was accompanied by an increase in the expression of pro-inflammatory cytokines, such as interferon-gamma (IFNγ), tumor necrosis factor-alpha (TNFα) and IL-6, in mice inoculated with MWCNTs, whether or not they had been immunized with OVA. A decrease in the expression of transforming growth factor-beta (TGFβ) was observed in the mice treated with MWCNTs, whereas the suppression of the expression of both TGFβ and IL-10 was observed in mice that had been both treated and immunized. The activation of the T lymphocyte response by the pro-inflammatory cytokines leads to an increase in antibody production to OVA, suggesting the important immunostimulatory effect of carbon nanotubes.     

Gold Nanoparticles Downregulate Interleukin‐1β‐Induced Pro‐Inflammatory Responses

Interleukin 1 beta (IL‐1β)‐dependent inflammatory disorders, such as rheumatoid arthritis and psoriasis, pose a serious medical burden worldwide, where patients face a lifetime of illness and treatment. Organogold compounds have been used since the 1930s to treat rheumatic and other IL‐1β‐dependent diseases and, though their mechanisms of action are still unclear, there is evidence that gold interferes with the transmission of inflammatory signalling. Here we show for the first time that citrate‐stabilized gold nanoparticles, in a size dependent manner, specifically downregulate cellular responses induced by IL‐1β both in vitro and in vivo. Our results indicate that the anti‐inflammatory activity of gold nanoparticles is associated with an extracellular interaction with IL‐1β, thus opening potentially novel options for further therapeutic applications.     

Broad‐Spectrum Antibacterial Activity of Carbon Nanotubes to Human Gut Bacteria

Carbon nanotubes (CNTs) hold promise in manufacturing, environmental, and biomedical applications, as well as food and agricultural industries. Previous observations have shown that CNTs have antimicrobial activity; however, the impact of CNTs to human gut microbes has not been investigated. Here, the antibacterial activity of CNTs against the microbes commonly encountered in the human digestion system—L. acidophilus, B. adolescentis, E. coli, E. faecalis, and S. aureus—are evaluated. The bacteria studied include pathogenic and non‐pathogenic, gram‐positive and negative, and both sphere and rod strains. In this study, CNTs, including single‐walled CNTs (SWCNTs, 1–3 μm), short and long multi‐walled CNTs (s‐MWCNTs: 0.5–2 μm; l‐MWCNTs: >50 μm), and functionalized multi‐walled CNTs (hydroxyl‐ and carboxyl‐modification, 0.5–2 μm), all have broad‐spectrum antibacterial effects. Notably, CNTs may selectively lyse the walls and membranes of human gut microbes, depending on not only the length and surface functional groups of CNTs, but also the shapes of the bacteria. The mechanism of antibacterial activity is associated with their diameter‐dependent piercing and length‐dependent wrapping on the lysis of microbial walls and membranes, inducing release of intracellular components DNA and RNA and allowing a loss of bacterial membrane potential, demonstrating complete destruction of bacteria. Thin and rigid SWCNT show more effective wall/membrane piercing on spherical bacteria than MWCNTs. Long MWCNT may wrap around gut bacteria, increasing the area making contact with the bacterial wall. This work suggests that CNTs may be broad‐spectrum and efficient antibacterial agents in the gut, and selective application of CNTs could reduce the potential hazard to probiotic bacteria.     

Tolerogenic Iron Oxide Nanoparticles in Type 1 Diabetes: Biodistribution and Pharmacokinetics Studies in Nonobese Diabetic Mice

Nanoparticle (NP) administration is among the most attractive approaches to exploit the synergy of different copackaged molecules for the same target. In this work, iron oxide NPs are surface‐engineered for the copackaging of the autoantigen proinsulin, a major target of adaptive immunity in type 1 diabetes (T1D), and 2‐(1′H‐indole‐3′‐carbonyl)‐thiazole‐4‐carboxylic acid methylester (ITE), a small drug conditioning a tolerogenic environment. Magnetic resonance imaging (MRI) combined with magnetic quantification are used to investigate NP biokinetics in nonobese diabetic (NOD) mice and control mice in different organs. Different NP biodistribution, with in particular enhanced kidney elimination and a stronger accumulation in the pancreas for prediabetic NOD mice, is observed. This is related to preferential NP accumulation in the pancreatic inflammatory zone and to enhancement of renal elimination by diabetic nephropathy. For both mouse strains, an MRI T2 contrast enhancement at 72 h in the liver, pancreas, and kidneys, and indicating recirculating NPs, is also found. This unexpected result is confirmed by magnetic quantification at different time points as well as by histological evaluation. Besides, such NPs are potential MRI contrast agents for early diagnosis of T1D.     

Cyclodextrin‐Derived Intrinsically Bioactive Nanoparticles for Treatment of Acute and Chronic Inflammatory Diseases

Inflammation is a common cause of many acute and chronic inflammatory diseases. A major limitation of existing anti‐inflammatory therapeutics is that they cannot simultaneously regulate pro‐inflammatory cytokine production, oxidative stress, and recruitment of neutrophils and macrophages. To overcome this limitation, nanoparticles (NPs) with multiple pharmacological activities are synthesized, using a chemically modified cyclic oligosaccharide. The manufacture of this type of bioactive, saccharide material‐based NPs (defined as LCD NP) is straightforward, cost‐effective, and scalable. Functionally, LCD NP effectively inhibits inflammatory response, oxidative stress, and cell migration for both neutrophils and macrophages, two major players of inflammation. Therapeutically, LCD NP shows desirable efficacies for the treatment of acute and chronic inflammatory diseases in mouse models of peritonitis, acute lung injury, and atherosclerosis. Mechanistically, the therapeutic benefits of LCD NP are achieved by inhibiting neutrophil‐mediated inflammatory macrophage recruitment and by preventing subsequent pro‐inflammatory events. In addition, LCD NP shows good safety profile in a mouse model. Thus, LCD NP can serve as an effective anti‐inflammatory nanotherapy for the treatment of inflammatory diseases mainly associated with neutrophil and macrophage infiltration.     

The Crystallinity and Aspect Ratio of Cellulose Nanomaterials Determine Their Pro‐Inflammatory and Immune Adjuvant Effects In Vitro and In Vivo

Nanocellulose is increasingly considered for applications; however, the fibrillar nature, crystalline phase, and surface reactivity of these high aspect ratio nanomaterials need to be considered for safe biomedical use. Here a comprehensive analysis of the impact of cellulose nanofibrils (CNF) and nanocrystals (CNC) is performed using materials provided by the Nanomaterial Health Implications Research Consortium of the National Institute of Environmental Health Sciences. An intermediary length of nanocrystals is also derived by acid hydrolysis. While all CNFs and CNCs are devoid of cytotoxicity, 210 and 280 nm fluorescein isothiocyanate (FITC)‐labeled CNCs show higher cellular uptake than longer and shorter CNCs or CNFs. Moreover, CNCs in the 200–300 nm length scale are more likely to induce lysosomal damage, NLRP3 inflammasome activation, and IL‐1β production than CNFs. The pro‐inflammatory effects of CNCs are correlated with higher crystallinity index, surface hydroxyl density, and reactive oxygen species generation. In addition, CNFs and CNCs can induce maturation of bone marrow–derived dendritic cells and CNCs (and to a lesser extent CNFs) are found to exert adjuvant effects in ovalbumin (OVA)‐injected mice, particularly for 210 and 280 nm CNCs. All considered, the data demonstrate the importance of length scale, crystallinity, and surface reactivity in shaping the innate immune response to nanocellulose.     

A New NLRP3 Inflammasome Inhibitor,Dioscin, Promotes Osteogenesis

Refractory periapical periodontitis, which is a persistent infection after root canal treatment, still has no effective treatment. Its most common pathogen is Enterococcus faecalis. Here, the precursor of phytosteroids, dioscin, is introduced to fight against the inflammation induced by Enterococcus faecalis. The findings suggest that dioscin inhibits the nuclear transport of NF‐κB and the expression of reactive oxygen species (ROS) induced by lipoteichoic acid from the Enterococcus faecalis. The decrease in mRNA and protein levels of NLRP3, Caspase‐1, and IL‐1β is observed in dioscin treated mouse macrophages. In the MC3T3‐E1 cells, dioscin also promotes the expression of osteogenic‐related factors, ALP, Runx2, and OCN. The increased formation of mineralized nodules after the application of dioscin further indicates that dioscin has the potential to promote osteogenesis. The above results suggest dioscin can be a potential root canal irrigation or root canal sealant for the treatment of refractory apical periodontitis.     

The poly(urethane-ionic liquid)/multi-walled carbon nanotubes composites

In the paper, a novel kind of imidazolium based poly(urethane-ionic liquid)/multi-walled carbon nanotubes (PUIL/MWCNT) composites was facilely prepared by uncovalent ways. The imidazolium based ionic liquid (IL) greatly improved the dispersion of pristine MWCNTs in PUIL by the π-cation interaction formed between the imidazolium cation and the π-electron of MWCNTs. The PUIL/MWCNT composites showed obviously increased modulus, glass transition temperature and tensile strength in comparison with PU/MWCNT composites. The thermal and mechanical properties of the PUIL/MWCNT composites presented significant increase with low load of the MWCNTs. It indicated the interactions between PUIL and MWCNTs played an important role to enhance the performances of the composites.     

The neuroprotective effect of a traditional herbal (kyung‐ok‐ko) on transient middle cerebral artery occlusion‐Induced ischemic rat brain

Kyung‐ok‐ko (KOK) has been used for the treatment of central nervous system disorders such as amnesia, dementia, and cerebral ischemia. However, the effects of KOK on transient ischemic‐induced neuronal damage are still unclear. We examined whether KOK improves functional recovery and has a neuroprotective effect on infarction volume after transient middle cerebral artery occlusion (MCAO). KOK (50, 100, and 200 mg/kg) was administered orally following reperfusion and twice per day for 14 days post‐MCAO. Infarction volume was measured using 2% 2‐3‐5 triphenylterazolium (TTC) staining at 14 days post‐MCAO and alteration in regional cerebral blood flow (rCBF) after KOK treatment was monitored. Functional improvement was evaluated using adhesive removal and treadmill tests at 1, 7, and 14 days post‐MCAO. Also, apoptotic cell death was assessed by terminal deoxynucleotidyl‐transferase mediated d‐UTP‐biotin nick end (TUNEL) in the peri‐infarction region. The protein level of inflammatory cytokines such as tumor necrosis factor‐α (TNF‐α), interleukin‐1α (IL‐1α), and interleukin‐1β (IL‐1β) was measured in the ischemic core, ischemic border zone, and contralateral hemisphere regions. The KOK‐treated group showed both reduced infarction volume and behavior tests demonstrated a significant improvement as compared to the control. Also, in the KOK‐treated group, rCBF was recovered to near normal levels. The apoptotic cells were significantly decreased as compared with the control group in the ischemic peri‐infarction area. Furthermore, the level of TNF‐α, IL‐1β, and IL‐1α was decreased. These results suggest that KOK may improve functional outcome by inhibiting inflammatory cytokines (TNF‐α, IL‐1β, and IL‐1α) in neuronal injury such as ischemic stroke.